From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752324Ab3FYXuf (ORCPT ); Tue, 25 Jun 2013 19:50:35 -0400 Received: from mx1.redhat.com ([209.132.183.28]:12828 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751693Ab3FYXue (ORCPT ); Tue, 25 Jun 2013 19:50:34 -0400 Message-ID: <51CA2CBF.70404@redhat.com> Date: Tue, 25 Jun 2013 19:50:23 -0400 From: Prarit Bhargava User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.17) Gecko/20110419 Red Hat/3.1.10-1.el6_0 Thunderbird/3.1.10 MIME-Version: 1.0 To: Thomas Gleixner CC: Linux Kernel , athorlton@sgi.com, CAI Qian Subject: Re: BUG: tick device NULL pointer during system initialization and shutdown References: <51C0AB09.2090605@redhat.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 06/24/2013 09:57 AM, Thomas Gleixner wrote: > On Tue, 18 Jun 2013, Prarit Bhargava wrote: > >> Similar panics reported during bringup here: >> >> http://lists.infradead.org/pipermail/linux-arm-kernel/2013-May/166205.html >> http://lkml.org/lkml/2013/5/8/342 >> >> I've seen this a few times on 3.10 based kernels. >> >> [ 175.842027] Disabling non-boot CPUs ... >> [ 475.827017] BUG: unable to handle kernel NULL pointer dereference at >> 0000000000000048 > > That looks like a stale bit in tick_broadcast_force_mask. > > Does the patch below fix it? > Thomas, Thanks for the patch. The reproducibility appears to be quite low. I'm seeing this roughly 1 time every six hours of continuous system reboots. I'm testing right now with your patch. I'll update the thread in a couple of days... P.